
February 2017
www.farmscanag.com
AM-74V1-4
16
Explanation of Components
EXPLANATION OF COMPONENTS
PRESSURE RELIEF VALVE (PRV)
(Farmscan Ag Part # AH-608/G)
The PRV is essential for safe and accurate operation of a positive displacement pump.
The PRV is used to set the maximum pressure available to the flow control valve and
protects the system by relieving excess pressure back to tank when the section controls
are switched off.
NOTE:
Failure to use a PRV in a spray system using a positive displacement pump may
result in pump damage.
FLOW CONTROL VALVE
(Farmscan Ag Part # AH-600/G)
The spray controller is designed to operate a DC motorised flow control valve fitted
downstream of the PRV, operating using either proportional or direct flow control to
regulate the main delivery line feeding the flow sensor and section control valves.
FLOW SENSOR
(Farmscan Ag Part # AA-230/A | 10-100L/min)
The flow sensor provides continuous feedback to the spray controller, which
regulates the flow control valve to maintain the required volume of liquid delivered
to the section valves.
NOTES:
All liquid delivered through the flow sensor must go to the section control valves only, i.e. no return
line back to tank or pump can be installed in front of the flow sensor.
The sprayer must operate within the minimum and maximum operating range of the flow sensor,
otherwise erratic and/ or inaccurate control may result.
Check required minimum and maximum flow rate BEFORE installing the equipment.
Alternative flow sensors are available.
Flow rate calculation:
Rate (L/Ha) x Speed (km/h) x Width (Metres) = L/Min
600
Example:
50L/Ha x 12 Kph x 12m = 12L/min
600